1. Chapter 22 Transportation Systems
What we’ll learn
Name the different types of land transportation.
Summarize the purpose of transportation subsystems.
Examine the purpose of a transmission.
Tell how oceans and inland waterways are used for transportation.
List the different types of ships.
Define the concept of intermodal transportation.
Discuss ways in which air and space transportation are used.
Identify different types of aircraft and spacecraft.
Explain how an airplane is lifted into the air.

2. Land Transportation

3. Transportation Systems
A transportation system is a way of moving people or products from place to place.
Transportation systems have inputs, processes, outputs, and feedback.
For example, inputs to a city bus system include bus drivers and fuel. Processes include driving the bus and loading passengers. The output is arrival at scheduled stops. Feedback includes comments from satisfied customers.

4. Transportation Systems
Transportation systems are interrelated.
Each system depends on the other systems.
Buses and cars, for example, take passengers to airports and ship docks.
Transportation systems are part of the larger technological, social, and environmental systems in our world.

5. Land Transportation
When you travel in a car, bus, or train, you are using a land transportation vehicle.
Land transportation also includes travel by bicycle, motorcycle, and subway.
Automobiles are an important part of our land transportation system.
However, you need more than just a car to get from place to place.
Roads, bridges, and service centers are just a few of the subsystems within a land transportation system that allow you to use your family car.

6. Mass Transportation
Mass transportation moves many people at one time and is available to the general public.
However, it is expensive to develop mass transportation systems that can serve a large country. That is one reason why the automobile has become an important part of our land transportation system.
Automobiles are for personal transportation, not mass transportation.

7. Mass Transportation
Mass transportation is sometimes slower and less convenient.
However, people who use mass transportation do not have to worry about parking their cars or paying for gas, parking tickets, or car insurance.

8. Automobiles Modern automobiles are quite different from early models.
However, your family car has at least two things in common with those early models.
Both have transmissions, and nearly all have front mounted engines.

9. Automobiles - Transmission
A car’s transmission contains gears and other parts that transfer power from the engine to the axles and wheels.
The gears work on the same principles as gears on a bicycle.
When you pedal up a hill, you shift into low gear because it takes more effort to pedal up the hill. The rear wheel moves more slowly.

10. Automobiles - Transmission
On level ground, it takes less effort to pedal, and the rear wheel of the bicycle turns more quickly.
A car’s engine operates best if you use a low gear while climbing a steep hill or when starting from a stop.
Using a high gear is best when driving on a flat road.

11. Automobiles - Driving Wheels
The power from your legs is transferred to your bicycle’s rear wheel with a chain. The rear wheel is a bicycle’s driving wheel.
A car does not use a chain. Instead, it transfers power with one or two metal shafts called “drive shafts.”
Most cars transfer power to the front wheels and are known as front-wheel drive cars.
Some cars transfer power to the rear wheels. They are rear-wheel drive cars.
Some send power to all four wheels. These cars are four-wheel drive, or all-wheel drive, cars.

12. Automobiles - Other Subsystems
An automobile has many subsystems. Besides the transmission and driving wheels, some subsystems include
those that provide structure and support (frame),
propulsion (engine),
and guidance (steering wheel).
Others are safety related (air bags).
Some cars have mapping computers that connect to GPS satellites.

13. Automobiles - Other Subsystems
Many of these subsystems are manufactured by outside suppliers.
The anti-lock braking system (ABS), for example, is not usually made by the same company that makes the car.
The CD player, tires, and windshield may also be manufactured by a different company.

14. Buses
Buses usually carry 30 or more passengers and are used for mass transportation between cities.
This is called “intercity transportation.”
Buses are also used for transportation within cities and for school transportation.
School systems in the United States alone use over 400,000 buses.

15. Buses - School Buses School buses were being used as early as 1920.
They made it possible to gather students together from small rural schools into one larger school with improved facilities.
Millions of students ride safe and sturdy buses to school each day.
Buses are made from strong steel to meet federal manufacturing requirements.
Seats and other support systems are specially designed for safety.
Many use diesel fuel, which would not burn as easily as gasoline if an unexpected leak should occur.

16. Buses - Intercity & Urban Buses
Intercity buses
Intercity buses are also powered by diesel engines.
These types of buses carry up to 64 seated passengers.
They are generally less expensive for passengers to ride than trains or airplanes.
They also make stops at smaller communities that are not served by trains and airplanes.
Urban Buses
Urban buses can carry more people than intercity buses because they allow some passengers to stand.
Use of urban buses eases traffic congestion and saves fuel.
They use about one-third as much fuel per passenger as do automobiles.

17. Trucks
Cities rely on trucks to supply them with food, fuel, furniture, and other products.
Trucks play an important role in transportation. They go directly from the supply location to the customer. Most trains, airplanes, and ships do not do that.

18. Trucks - Types of Trucks
We use hundreds of different kinds of trucks.
Most are diesel powered, but gasoline engines are also used.
Some commercial trucks are as small as pickup trucks.
Others are as large as the 18-wheel semi-trailer trucks that carry cargo on interstate highways. These large trucks are also called tractor-trailers.
There is no such thing as a standard truck, but there are three general types:
light duty,
Panel and pickup trucks are examples of light-duty trucks.
medium duty, and
Medium-duty trucks are used locally and include sanitation trucks, soft drink delivery trucks, and heating oil trucks.
heavy duty.
Heavy-duty trucks carry large loads, and an 18-wheel tractor-trailer is one type.

19. Trucks - Wind Deflectors
The flat front and square shape of many trucks present a large surface that the air can press against.
This means that the trucks waste fuel.
Some manufacturers place a wind deflector on the tractor’s roof.
A deflector directs the air around the truck, which reduces resistance and saves fuel.

20. Locomotives Railroads earn most of their money by hauling freight.
They deliver bulky items like coal and iron ore. They also carry things such as automobiles and television sets. Some are over 200 cars long.
Trains also carry passengers. In some countries, trains carry up to 50 percent of intercity travelers.
Commuter and subway trains transport workers, tourists, students, shoppers, and others to their daily destinations.
They are also part of the mass transportation network.

21. Locomotives - High-Speed Trains
The newest all-electric locomotives, called bullet trains, travel at high speeds.
The speed and the pointed shape of the locomotive’s nose inspired its name.
Japan’s Shinkansen was the first bullet train in 1964.
The bullet train in the United States is the Acela Express, for acceleration and excellence.
Several all-electric stainless steel trains entered service in the year 2000.
Each six-coach train can carry over 300 passengers at speeds up to 150 mph.

22. Locomotives - Maglev Trains
Another new kind of train does not roll on wheels. It does not even touch the ground. The train is called a maglev train.
Maglev stands for “magnetic levitation.”
The forces of magnetic attraction and repulsion allow the train to float, or levitate, less than one inch above its guideway, or path. The same forces interact to move the trains.

23. Locomotives - Maglev Trains
Maglevs are very quiet and produce almost no vibration.
However, they are expensive to construct.
The first maglev to enter commercial service runs on a 22-mile line to the Shanghai airport in China.
The train’s highest speed during the trip is normally about 260 miles per hour.
It was built in Germany and began passenger service in 2004.

24. Pipelines
When you turn on a faucet to get a drink of water, you are using a transportation system.
Some cargo, like water, oil, and natural gas, travels long distances through pipelines.
Pipes may be as small as two inches in diameter or as large as 15 feet in diameter.
Most pipelines are buried in the ground.
Pipelines require service facilities such as pumping and control stations.
The stations are located along the pipeline and keep the cargo moving. When the cargo is made of particles, such as gravel, it is mixed with liquids to form a “slurry.”
The pumps then force the material through the pipeline.

25. Water Transportation

26. Waterways Water has provided transportation routes for centuries.
Oceans, rivers, lakes, and other navigable waterways have made natural routes between cities, states, countries, and continents.
A navigable waterway is a lake or river that is deep and wide enough to allow ships and boats to pass.
Engineers can also construct canals through which boats and ships can pass.
The Suez Canal in Egypt connects the Mediterranean Sea with the Red Sea, allowing ships to carry cargo back and forth between Europe and Asia.
It usually costs less to transport goods by water than by rail, highway, or air. Whenever possible, people try to save as much money as they can by transporting products the cheapest way.

27. Boats and Ships A small, open vessel is called a “boat.”
A large, deep-water vessel is called a ship.
There are about 24,000 ships in the world.
There are three general types of water transportation vessels.
Passenger vessels that carry people are one type.
Cargo ships are another type. They transport oil, grain, iron ore, automobiles, and many other products.
Specialty craft include every other type, such as river barges used for transporting coal and other goods, tugboats for pulling large ships into dock, and icebreakers.

28. Overseas Cargo Ships deliver most of the overseas cargo.
To transport by ship,
Docks with special loading and unloading equipment.
Properly trained people to operate the ship.
Good communications for weather data and other information.
They are all necessary for the entire system to operate efficiently.

29. Heavy Ships
For many centuries, people used sailing ships to haul cargo and passengers.
The ships of the 1800s had displacements of about 1,200 tons.
Displacement is a measure of how much water a ship and its cargo push aside as the ship floats.
It is an indication of the ship’s size. Today an average cargo ship might have a displacement of 21,000 tons.
A heavy ship is difficult to move, so today’s ships are pushed by powerful engines. Ocean liners and cargo ships often use gas turbine or diesel engines.

31. Heavy Ships
It is not unusual for a large modern ship to displace 100,000 tons.
That means it is about 80 times bigger than a ship of the 1800s.
Very large ships called supertankers transport oil across oceans in storage tanks.
Their displacements are as high as 500,000 tons.

32. Intermodal Transportation
When two or more modes of transportation are used together to move people or cargo more efficiently, it is called intermodal transportation.
Moving People
To understand how intermodal transportation helps move people, imagine that you are going to take a cruise.
To get to the city where you will board ship, you need to take an airplane.
In order to reach the airport, you might take a bus to a subway station, and then travel to the airport via subway train.
You might also drive your own car or take an airport shuttle.
Different systems have been organized to work together to help you.

33. Intermodal Transportation
There is a bus stop near the subway station, a subway stop at the airport, and a taxi to take you from the airport in the coastal city to the cruise ship.
Moving Cargo
Cargo is moved most efficiently when it is packed into large containers.
When a product travels overseas, the containers are loaded on ships called containerships.
Loading and unloading is easy because the containers are usually the same size and the same shape.
Containers can then be loaded onto a train. The products do not have to be unpacked and then repacked.
Some containers are designed as truck semi-trailers. They ride on trains to a terminal, where they are then attached to truck tractors. They continue their journey on the highway.
Because intermodal transportation is so efficient, it saves time and money.

34. Air and Space Transportation

35. Air Transportation
Transportation by air takes place in airplanes, helicopters, and lighter-than-air craft.
Hang gliders and sailplanes are used for recreation.
Military airplanes are used for defense.
Airplanes are the most important part of our air transportation system.
However, many other components are necessary for safe air travel. For example, we need airports, training programs, and radar.
Many airplanes are in the air at the same time. This is why air travel is our most complex transportation system and is regulated by the government.

36. Airplanes
Did you ever wonder how something as heavy as an airplane could get off the ground?
The secret is in the shape of the airplane’s wing.
As the airplane approaches the runway, it gathers speed and air rushes over the wing.
The shape of the wing causes the air to travel faster over its upper surface. This reduces air pressure above the wing. It also helps increase the pressure on the wing’s lower surface, pushing it upward and creating lift. Almost like magic, the airplane rises.

37. Commercial Airplanes
Many important airplanes were built and flown after the Wright brothers’ first flight in 1903.
One of the most important airplanes was the 1935 DC-3, which had two gasoline engines.
It was the first commercial airplane as it made a profit by carrying just passengers.
The Boeing 707 came out in 1958 and carried 179 passengers, a huge number at the time.

38. Commercial Airplanes
In following years the number of airline passengers increased so much that manufacturers decided to build jumbo jets, very large jet airplanes that can carry about 500 passengers.
The first was the Boeing 747. Because jumbo jets have such powerful engines, they can lift more weight than other airplanes.
This allows them to carry a lot of fuel. As a result, they can stay up in the air for a long time.
Jumbo jets can fly non-stop from Cincinnati to London and from Detroit to Tokyo.

39. Smaller Jets &Cargo Planes
Smaller jet aircraft, like the two-engine Canadair RJ-200, are used on shorter flights between smaller cities.
They use less fuel and do not need a long runway to take off.
Some airplanes carry only cargo. However, even the biggest airplane can carry only a fraction of what a ship or train can haul.
A Boeing 747 can carry 100 tons of cargo.
Transport by air can be very expensive. Therefore only lightweight items, such as mail and electronics, are usually shipped by air.

40. Helicopters
A helicopter is an aircraft with one or two rotors that allow it to lift straight up.
The twirling blades of the rotor create lift. Some helicopters also have small tail rotors to keep them from spinning out of control.
Helicopters can be as small as a one-person machine or as large as a cargo-carrying helicopter capable of lifting ten tons.
Passenger-carrying helicopters connect some large cities with major airports.
Some helicopters deliver parts to construction sites. Others are used to check on traffic or to transport people to hospitals.

41. Lighter-than-Air Craft
Lighter-than-air craft include aircraft
such as dirigibles, blimps, and airships.
Helium lifts them into the air, and gasoline engines turn propellers to move them forward.
The engines are located in gondolas, or cars, that are suspended from the craft.
The passenger compartment is located in a separate gondola.
A hot-air balloon is also a lighter-than-air craft. It uses large torches to heat the air inside a huge nylon bag.
Hot air weighs less than cooler air, so the balloon rises. The pilot controls the balloon by ascending or descending into wind currents.

42. Space Vehicles
The National Aeronautics and Space Administration (NASA) is responsible for regulating and directing the entire U.S. space program. This includes the space shuttles and vehicles for exploration.

43. Space Shuttles
The first space shuttle that went into orbit was the Columbia in 1981.
On a typical mission, a space shuttle with four astronauts orbits 115 miles above the earth. Each flight carries cargo, called a payload, in the large cargo bay.
The payload can weigh up to 65,000 pounds.
Shuttle speed is about 17,000 miles per hour.
Once in orbit, an astronaut opens the cargo bay doors, which may contain a communications satellite.
The astronaut controls a 50-foot mechanical arm that grabs the satellite and releases it a safe distance from the shuttle. The arm can also grab satellites already in orbit.

44. Shuttle Missions
The space shuttle can also carry a complete scientific laboratory in the cargo bay.
However, many laboratory experiments are now done on the International Space Station (ISS).
A shuttle mission can also include carrying supplies to the ISS.
To return to earth, the astronauts fire small rockets to slow down the space shuttle. It re-enters the atmosphere and glides toward a landing strip.

45. Shuttle Missions
Space shuttle astronauts have a very dangerous job, and several have been lost during in-flight failures.
For example, seven astronauts on the Challenger in 1986 and another seven on the Columbia in 2003 perished during their missions.
Spacecraft can also travel without astronauts. These ships consist of hollow containers mounted on booster rockets. The hollow containers usually carry satellites for communication or scientific research.
Once a spacecraft is in orbit, its container opens, and the satellite is put into position. The satellite then begins orbiting on its own.